PROJECT SUMMARY The Asian tiger mosquito Aedes albopictus is the world?s most successful invasive mosquito species that in the last four decades has invaded all continents except Antarctica. Ae. albopictus is a competent vector of various arboviral illnesses including dengue fever?the leading arboviral disease of the 21st century?and Zika fever?the disease that caused an epidemic outbreak in Brazil in 2015 with 1.5 million cases of the disease and more than 5 thousand cases of uncommon microcephaly in newborns. As a competent vector of Zika virus, Ae. albopictus has the potential to spread this dangerous disease further north because of its remarkable ability to develop a photoperiodic diapause in the temperate climate. This project will develop a chromosome- based reference genome assembly for Ae. albopictus and will test if adaptations to the temperate climate are associated with structural variations in the Ae. albopictus genome. Toward this end, we propose the following specific aims: 1) develop a high-quality genome assembly for a North American strain of Ae. albopictus using PacBio sequencing, 2) construct a physical map for the Ae. albopictus genome based on fluorescent in situ hybridization (FISH) on mitotic chromosomes, and 3) determine structural genome variation in temperature and tropical strains of Ae. albopictus using 10X Genomics sequencing and FISH. Our long-term goal is to understand the genetic basis of the incredible phenotypic plasticity of Ae. albopictus that helps this mosquito to rapidly spread around the globe. We envision that the availability of the high-quality reference genome assembly for the North American strain of Ae. albopictus will stimulate further genetic studies aimed at preventing mosquito-borne disease transmission.